Experimental investigation of domain switching criterion for soft lead zirconate titanate piezoceramics under coaxial proportional electromechanical loading

摘要

In this experimental work, "soft" lead zirconate titanate specimens in an initially unpoled state were subjected to combined electromechanical loading, in which a compressive stress and a parallel, proportional electric field were applied simultaneously. By changing the ratio of stress to the electric field between tests, a series of nonlinear polarization and strain responses were obtained. An attempt has been made to explain the experimental findings by simultaneously taking into account the contributions of dielectric response, elastic deformation, piezoeffects, and irreversible domain switching. Initial domain switching surfaces in the biaxial stress and electric field space were determined based on an offset method. Several switching conditions existing in the literature were summarized and compared with the experimental data obtained in this work. Such an investigation may serve to calibrate and validate existing constitutive models concerning the large-signal nonlinear behavior of piezoceramics.